Testing Methods And Procedures For SDT Technical Field

ABSTRACT

Multiple techniques for testing a UE by a Test Equipment (TE) are disclosed. A TE configures with a procedure of performance testing of data transmission to be performed while the UE is in an inactive state. The TE performs the performance testing, wherein the procedure includes at least one of: triggering the data transmission while the UE is in the inactive state; transmitting one or more test data packages; controlling time that the UE starts to transmit, while in the inactive state, payload corresponding to the test data package(s); verifying whether or not conditions for the data transmission are met; or determining whether or not the UE passed the performance testing, based on a result of the verification of whether or not conditions for the data transmission are met. The UE performs the data transmission and can send measurement results. There are multiple conditions that can be tested.

Exemplary embodiments herein relate generally to testing devices forwireless communications and using SDT. The methods presented can, forexample, be used for verification of timing advance (TA) validationbetween user equipment (UEs) and system simulators.

BACKGROUND

Small Data Transmission (SDT) is a feature introduced in 3GPP Rel. 17(third generation partnership project, release 17) for 5G (fifthgeneration, also referred to as new radio, NR), where small packets ofdata can be transmitted while the UE (user equipment, a wireless device)is in RRC (Radio Resource Control) inactive mode. This feature inintended as an energy-saving feature, since the UE can stay longerperiods of time in the RRC inactive mode, which uses less power thanwhen the UE is in an RRC connected mode.

There are two main different implementations of SDT. In oneimplementation, the UE transmits small transport blocks as part of therandom-access procedure while in RRC inactive mode. This type of SDTtransmission is referred to herein as RA-SDT (Random Access-SDT). In theother implementation, a configured grant resource is allocated for theUE to transmit while in the RRC inactive mode. The last type of SDTtransmission is referred to herein as CG-SDT (configured grant-SDT).

In order for the CG-SDT to function properly, there is a mechanism forthe UE to keep synchronicity in UL (uplink, from the UE to the network).Such a mechanism can be used during testing, when the timing advance(TA) used by the UE is being validated by the UE.

Furthermore, for TA validation, the UE should be tested to ensure itmeets multiple criteria.

BRIEF SUMMARY

This section is intended to include examples and is not intended to belimiting.

In an exemplary embodiment, a method is disclosed that includesconfiguring a user equipment, by transmission from a testing equipment,at least part of a procedure of performance testing of data transmissionto be performed while the user equipment is in a radio resource controlinactive state. The method includes performing, by the testingequipment, the at least part of the procedure of performance testing ofdata transmission while the user equipment is in the radio resourcecontrol inactive state; wherein the at least part of the procedureincludes at least one of: triggering the data transmission while theuser equipment is in the radio resource control inactive state;transmitting one or more test data packages; controlling time that theuser equipment starts to transmit, while in the radio resource controlinactive state, payload corresponding to at least one of the one or moretest data packages; verifying whether or not conditions for the datatransmission are met; or determining whether or not the user equipmentpassed the performance testing, based on a result of the verification ofwhether or not conditions for the data transmission are met.

An additional exemplary embodiment includes a computer program,comprising code for performing the method of the previous paragraph,when the computer program is run on a processor. The computer programaccording to this paragraph, wherein the computer program is a computerprogram product comprising a computer-readable medium bearing computerprogram code embodied therein for use with a computer. Another exampleis the computer program according to this paragraph, wherein the programis directly loadable into an internal memory of the computer.

An exemplary apparatus includes one or more processors and one or morememories including computer program code. The one or more memories andthe computer program code are configured to, with the one or moreprocessors, cause the apparatus at least to: configure a user equipment,by transmission from a testing equipment, at least part of a procedureof performance testing of data transmission to be performed while theuser equipment is in a radio resource control inactive state; andperform, by the testing equipment, the at least part of the procedure ofperformance testing of data transmission while the user equipment is inthe radio resource control inactive state; wherein the at least part ofthe procedure includes at least one of: triggering the data transmissionwhile the user equipment is in the radio resource control inactivestate; transmitting one or more test data packages; controlling timethat the user equipment starts to transmit, while in the radio resourcecontrol inactive state, payload corresponding to at least one of the oneor more test data packages; verifying whether or not conditions for thedata transmission are met; or determining whether or not the userequipment passed the performance testing, based on a result of theverification of whether or not conditions for the data transmission aremet.

An exemplary computer program product includes a computer-readablestorage medium bearing computer program code embodied therein for usewith a computer. The computer program code includes: code forconfiguring a user equipment, by transmission from a testing equipment,at least part of a procedure of performance testing of data transmissionto be performed while the user equipment is in a radio resource controlinactive state; and code for performing, by the testing equipment, theat least part of the procedure of performance testing of datatransmission while the user equipment is in the radio resource controlinactive state; wherein the at least part of the procedure includes atleast one of: triggering the data transmission while the user equipmentis in the radio resource control inactive state; transmitting one ormore test data packages; controlling time that the user equipment startsto transmit, while in the radio resource control inactive state, payloadcorresponding to at least one of the one or more test data packages;verifying whether or not conditions for the data transmission are met;or determining whether or not the user equipment passed the performancetesting, based on a result of the verification of whether or notconditions for the data transmission are met.

In another exemplary embodiment, an apparatus comprises means forperforming: configuring a user equipment, by transmission from a testingequipment, at least part of a procedure of performance testing of datatransmission to be performed while the user equipment is in a radioresource control inactive state; and performing, by the testingequipment, the at least part of the procedure of performance testing ofdata transmission while the user equipment is in the radio resourcecontrol inactive state; wherein the at least part of the procedureincludes at least one of: triggering the data transmission while theuser equipment is in the radio resource control inactive state;transmitting one or more test data packages; controlling time that theuser equipment starts to transmit, while in the radio resource controlinactive state, payload corresponding to at least one of the one or moretest data packages; verifying whether or not conditions for the datatransmission are met; or determining whether or not the user equipmentpassed the performance testing, based on a result of the verification ofwhether or not conditions for the data transmission are met.

In an exemplary embodiment, a method is disclosed that includesreceiving, at a user equipment, a configuration of at least part of aprocedure of performance testing of data transmission, the procedure tobe performed while the user equipment is in a radio resource controlinactive state. The method also includes performing, at the userequipment, based on the configuration, the at least part of a procedureof performance testing of data transmission while the user equipment isin the radio resource control inactive state, wherein the at least partof the procedure includes at least one of: receiving signaling oftriggering the data transmission; receiving one or more test datapackages; starting to transmit payload corresponding to at least one ofthe received one or more test data packages in radio resource controlinactive state, based on the configuration; or transmitting one or moremeasurement results based on one or more corresponding measurements madeat the user equipment.

An additional exemplary embodiment includes a computer program,comprising code for performing the method of the previous paragraph,when the computer program is run on a processor. The computer programaccording to this paragraph, wherein the computer program is a computerprogram product comprising a computer-readable medium bearing computerprogram code embodied therein for use with a computer. Another exampleis the computer program according to this paragraph, wherein the programis directly loadable into an internal memory of the computer.

An exemplary apparatus includes one or more processors and one or morememories including computer program code. The one or more memories andthe computer program code are configured to, with the one or moreprocessors, cause the apparatus at least to: receiving, at a userequipment, a configuration of at least part of a procedure ofperformance testing of data transmission, the procedure to be performedwhile the user equipment is in a radio resource control inactive state;and performing, at the user equipment, based on the configuration, theat least part of a procedure of performance testing of data transmissionwhile the user equipment is in the radio resource control inactivestate, wherein the at least part of the procedure includes at least oneof: receiving signaling of triggering the data transmission; receivingone or more test data packages; starting to transmit payloadcorresponding to at least one of the received one or more test datapackages in radio resource control inactive state, based on theconfiguration; or transmitting one or more measurement results based onone or more corresponding measurements made at the user equipment.

An exemplary computer program product includes a computer-readablestorage medium bearing computer program code embodied therein for usewith a computer. The computer program code includes: code for receiving,at a user equipment, a configuration of at least part of a procedure ofperformance testing of data transmission, the procedure to be performedwhile the user equipment is in a radio resource control inactive state;and code for performing, at the user equipment, based on theconfiguration, the at least part of a procedure of performance testingof data transmission while the user equipment is in the radio resourcecontrol inactive state, wherein the at least part of the procedureincludes at least one of: receiving signaling of triggering the datatransmission; receiving one or more test data packages; starting totransmit payload corresponding to at least one of the received one ormore test data packages in radio resource control inactive state, basedon the configuration; or transmitting one or more measurement resultsbased on one or more corresponding measurements made at the userequipment.

In another exemplary embodiment, an apparatus comprises means forperforming: receiving, at a user equipment, a configuration of at leastpart of a procedure of performance testing of data transmission, theprocedure to be performed while the user equipment is in a radioresource control inactive state; and performing, at the user equipment,based on the configuration, the at least part of a procedure ofperformance testing of data transmission while the user equipment is inthe radio resource control inactive state, wherein the at least part ofthe procedure includes at least one of: receiving signaling oftriggering the data transmission; receiving one or more test datapackages; starting to transmit payload corresponding to at least one ofthe received one or more test data packages in radio resource controlinactive state, based on the configuration; or transmitting one or moremeasurement results based on one or more corresponding measurements madeat the user equipment.

In an exemplary embodiment, a method is disclosed that includesconfiguring a user equipment, by transmission from a testing equipment,at least part of a procedure to be performed while the user equipment isin a radio resource control inactive state. The method includesperforming, by the testing equipment, the at least part of the procedureof performance testing of data transmission while the user equipment isin the radio resource control inactive state, wherein the at least partof the procedure is configured to start with a first transmit powerlevel, which is changed to a second transmit power level during ameasurement window to be used at the user equipment for measuring one ormore reference signals, and the at least part of the procedure isconfigured to change transmission power back to the first power levelwhen the user equipment is expected to perform measurement in themeasurement window. The method also includes verifying whether or notone or more conditions for the data transmission are met.

An additional exemplary embodiment includes a computer program,comprising code for performing the method of the previous paragraph,when the computer program is run on a processor. The computer programaccording to this paragraph, wherein the computer program is a computerprogram product comprising a computer-readable medium bearing computerprogram code embodied therein for use with a computer. Another exampleis the computer program according to this paragraph, wherein the programis directly loadable into an internal memory of the computer.

An exemplary apparatus includes one or more processors and one or morememories including computer program code. The one or more memories andthe computer program code are configured to, with the one or moreprocessors, cause the apparatus at least to: configuring a userequipment, by transmission from a testing equipment, at least part of aprocedure to be performed while the user equipment is in a radioresource control inactive state; performing, by the testing equipment,the at least part of the procedure of performance testing of datatransmission while the user equipment is in the radio resource controlinactive state, wherein the at least part of the procedure is configuredto start with a first transmit power level, which is changed to a secondtransmit power level during a measurement window to be used at the userequipment for measuring one or more reference signals, and the at leastpart of the procedure is configured to change transmission power back tothe first power level when the user equipment is expected to performmeasurement in the measurement window; and verifying whether or not oneor more conditions for the data transmission are met.

An exemplary computer program product includes a computer-readablestorage medium bearing computer program code embodied therein for usewith a computer. The computer program code includes: code forconfiguring a user equipment, by transmission from a testing equipment,at least part of a procedure to be performed while the user equipment isin a radio resource control inactive state; code for performing, by thetesting equipment, the at least part of the procedure of performancetesting of data transmission while the user equipment is in the radioresource control inactive state, wherein the at least part of theprocedure is configured to start with a first transmit power level,which is changed to a second transmit power level during a measurementwindow to be used at the user equipment for measuring one or morereference signals, and the at least part of the procedure is configuredto change transmission power back to the first power level when the userequipment is expected to perform measurement in the measurement window;and code for verifying whether or not one or more conditions for thedata transmission are met.

In another exemplary embodiment, an apparatus comprises means forperforming: configuring a user equipment, by transmission from a testingequipment, at least part of a procedure to be performed while the userequipment is in a radio resource control inactive state; performing, bythe testing equipment, the at least part of the procedure of performancetesting of data transmission while the user equipment is in the radioresource control inactive state, wherein the at least part of theprocedure is configured to start with a first transmit power level,which is changed to a second transmit power level during a measurementwindow to be used at the user equipment for measuring one or morereference signals, and the at least part of the procedure is configuredto change transmission power back to the first power level when the userequipment is expected to perform measurement in the measurement window;and verifying whether or not one or more conditions for the datatransmission are met.

In an exemplary embodiment, a method is disclosed that includesconfiguring a user equipment, by transmission from a testing equipment,at least part of a procedure to be performed while the user equipment isin a radio resource control inactive state. The method includesperforming, by the testing equipment, the at least part of the procedureof performance testing of data transmission while the user equipment isin the radio resource control inactive state, the performing comprisingtransmitting first and second power levels, at least the second powerlevel transmitted during a first measurement window to be used by theuser equipment for measuring one or more reference signals. The methodfurther includes verifying whether or not conditions for the datatransmission are met, wherein in response to a validation condition fora timing advance is not being satisfied. The method includestransmitting by the testing equipment a third power level before a startof a second measurement window to be used at the user equipment formeasuring one or more reference signal. The method includes, in responseto the second measurement window starting, transmitting by the testingequipment transmits a fourth power level; and verifying conditions forthe data transmission are met for the third and fourth power levels.

An additional exemplary embodiment includes a computer program,comprising code for performing the method of the previous paragraph,when the computer program is run on a processor. The computer programaccording to this paragraph, wherein the computer program is a computerprogram product comprising a computer-readable medium bearing computerprogram code embodied therein for use with a computer. Another exampleis the computer program according to this paragraph, wherein the programis directly loadable into an internal memory of the computer.

An exemplary apparatus includes one or more processors and one or morememories including computer program code. The one or more memories andthe computer program code are configured to, with the one or moreprocessors, cause the apparatus at least to: configure a user equipment,by transmission from a testing equipment, at least part of a procedureto be performed while the user equipment is in a radio resource controlinactive state; perform, by the testing equipment, the at least part ofthe procedure of performance testing of data transmission while the userequipment is in the radio resource control inactive state, theperforming comprising transmitting first and second power levels, atleast the second power level transmitted during a first measurementwindow to be used by the user equipment for measuring one or morereference signals; verify whether or not conditions for the datatransmission are met, wherein in response to a validation condition fora timing advance is not being satisfied; transmit by the testingequipment a third power level before a start of a second measurementwindow to be used at the user equipment for measuring one or morereference signal; in response to the second measurement window starting,transmit by the testing equipment transmits a fourth power level; andverifying conditions for the data transmission are met for the third andfourth power levels.

An exemplary computer program product includes a computer-readablestorage medium bearing computer program code embodied therein for usewith a computer. The computer program code includes: code forconfiguring a user equipment, by transmission from a testing equipment,at least part of a procedure to be performed while the user equipment isin a radio resource control inactive state; code for performing, by thetesting equipment, the at least part of the procedure of performancetesting of data transmission while the user equipment is in the radioresource control inactive state, the performing comprising transmittingfirst and second power levels, at least the second power leveltransmitted during a first measurement window to be used by the userequipment for measuring one or more reference signals; code forverifying whether or not conditions for the data transmission are met,wherein in response to a validation condition for a timing advance isnot being satisfied; code for transmitting by the testing equipment athird power level before a start of a second measurement window to beused at the user equipment for measuring one or more reference signal;code for in response to the second measurement window starting,transmitting by the testing equipment transmits a fourth power level;and code for verifying conditions for the data transmission are met forthe third and fourth power levels.

In another exemplary embodiment, an apparatus comprises means forperforming: configuring a user equipment, by transmission from a testingequipment, at least part of a procedure to be performed while the userequipment is in a radio resource control inactive state; performing, bythe testing equipment, the at least part of the procedure of performancetesting of data transmission while the user equipment is in the radioresource control inactive state, the performing comprising transmittingfirst and second power levels, at least the second power leveltransmitted during a first measurement window to be used by the userequipment for measuring one or more reference signals; verifying whetheror not conditions for the data transmission are met, wherein in responseto a validation condition for a timing advance is not being satisfied;transmitting by the testing equipment a third power level before a startof a second measurement window to be used at the user equipment formeasuring one or more reference signal; in response to the secondmeasurement window starting, transmitting by the testing equipmenttransmits a fourth power level; and verifying conditions for the datatransmission are met for the third and fourth power levels.

BRIEF DESCRIPTION OF THE DRAWINGS

In the attached Drawing Figures:

FIG. 1 is a block diagram of one possible and non-limiting exemplarysystem in which the exemplary embodiments may be practiced;

FIG. 2 is a signaling diagram illustrating a procedure for verificationof the UL timing requirements of a UE;

FIG. 3 is a signaling diagram illustrating OTA TST command for testloops;

FIG. 4 illustrates a signaling and time diagram for a first exemplarymethod (Method 1) using a test loop for testing SDT sessions using apure loopback mode, in accordance with an exemplary embodiment;

FIG. 4A is a logic flow diagram illustrating a flowchart for a decisiontree on what SDT procedure, if any, to perform based on differentparameters, in accordance with an exemplary embodiment;

FIG. 5 illustrates a signaling and time diagram for a second exemplarymethod (Method 2) using test loop for testing SDT sessions supplementedby AT command(s) to trigger an SDT session, in accordance with anexemplary embodiment;

FIG. 6 illustrates a signaling and time diagram for an example using anAT command alone to send a predefined SDT test package, in accordancewith an exemplary embodiment;

FIG. 7 , split into FIG. 7A and FIG. 7B, illustrates diagrams showingtesting method used for random access procedures, where FIG. 7Aillustrates a Test 1 and FIG. 7B illustrates a Test 2;

FIG. 8 , spread over FIGS. 8A and 8B, is a sequence diagram describingthe test case steps for verification of TA validation of CG-SDT in anexemplary embodiment; and

FIG. 9 illustrates an example of SS power over time for the testprocedure as used in FIG. 8 , in an exemplary embodiment.

DETAILED DESCRIPTION OF THE DRAWINGS

Abbreviations that may be found in the specification and/or the drawingfigures are defined below, at the end of the detailed descriptionsection.

The word “exemplary” is used herein to mean “serving as an example,instance, or illustration.” Any embodiment described herein as“exemplary” is not necessarily to be construed as preferred oradvantageous over other embodiments. All of the embodiments described inthis Detailed Description are exemplary embodiments provided to enablepersons skilled in the art to make or use the invention and not to limitthe scope of the invention which is defined by the claims.

When more than one drawing reference numeral, word, or acronym is usedwithin this description with “/”, and in general as used within thisdescription, the “/” may be interpreted as “or”, “and”, or “both”.

As used herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”,“comprising”, “has”, “having”, “includes” and/or “including”, when usedherein, specify the presence of stated features, elements, and/orcomponents etc., but do not preclude the presence or addition of one ormore other features, elements, components and/or combinations thereof.

For ease of reference, the rest of the text is divided into sections.The section headings are merely exemplary.

I. Exemplary System

The exemplary embodiments herein describe techniques for verification ofthe UE behavior by a system simulator in an RRC inactive state,including timing advance validation for CG-SDT transmissions, or othertypes of SDT transmissions, like RA-SDT. Additional description of thesetechniques is presented after a system into which the exemplaryembodiments may be used is described.

Turning to FIG. 1 , this figure shows a block diagram of one possibleand non-limiting exemplary system in which the exemplary embodiments maybe practiced. A user equipment (UE) 110 is in wireless communicationwith a system simulator (SS) 170. The UE 110 may be a device under test(DUT), and the SS 170 may be a test equipment or possibly be referred toby other names. The terms SS and test equipment are exchangeable in thisdocument. Regardless, the SS 170 performs a limited set of functions ofa base station intended for the test purpose, such as a gNB (a 5G basestation) or an eNB (an LTE base station), as well as other functionsthat are specific to testing methods.

The UE 110 is a wireless, typically mobile device that can access awireless network. The UE 110 includes circuitry comprising one or moreprocessors 120, one or more memories 125, one or more network (N/W)interfaces (I/Fs) 141, and one or more transceivers 130 interconnectedthrough one or more buses 127. Each of the one or more transceivers 130includes a receiver, Rx, 132 and a transmitter, Tx, 133. The one or morebuses 127 may be address, data, or control buses, and may include anyinterconnection mechanism, such as a series of lines on a motherboard orintegrated circuit, fiber optics or other optical communicationequipment, and the like. The one or more transceivers 130 are connectedto one or more antennas 128. The one or more memories 125 includecomputer program code 123. The N/W I/F(s) may be used to communicate viawired communications, such as

The UE 110 includes a control module 140, comprising one of or bothparts 140-1 and/or 140-2, which may be implemented in a number of ways.The control module 140 may be implemented in hardware as control module140-1, such as being implemented as part of the one or more processors120. The control module 140-1 may be implemented also as an integratedcircuit or through other hardware such as a programmable gate array. Inanother example, the control module 140 may be implemented as controlmodule 140-2, which is implemented as computer program code 123 and isexecuted by the one or more processors 120. For instance, the one ormore memories 125 and the computer program code 123 may be configuredto, with the one or more processors 120, cause the user equipment 110 toperform one or more of the operations as described herein. The UE 110communicates with SS 170 via a wireless link or via a cable between theantenna connectors 111. The test setup of FIG. 1 may also include aphysical (using cables) digital interface between the DUT and the SS 170which is used by the SS to provide test commands to the DUT, whichinclude AT commands or other proprietary methods of control for testpurposes. This is illustrated by a link 143 between the networkinterfaces 141 (in the UE) and 161 (in the SS 170, and described below).

The SS 170 acts like a base station, which typically provides access bywireless devices such as the UE 110 to a wireless network. Herein, theSS 170 may be assumed to act as a gNB, although other options arepossible.

The SS 170 includes circuitry comprising one or more processors 152, oneor more memories 155, one or more network interfaces (N/W I/F(s)) 161,and one or more transceivers 160 interconnected through one or morebuses 157. Each of the one or more transceivers 160 includes a receiver,Rx, 162 and a transmitter, Tx, 163. The one or more transceivers 160 areconnected to one or more antennas 158. The one or more memories 155include computer program code 153. The one or more network interfaces161 may communicate using a digital link 143 for use by the SS 170 toprovide test commands to the DUT, which may include AT commands.

The SS 170 includes a control module 150, comprising one of or bothparts 150-1 and/or 150-2, which may be implemented in a number of ways.The control module 150 may be implemented in hardware as control module150-1, such as being implemented as part of the one or more processors152. The control module 150-1 may be implemented also as an integratedcircuit or through other hardware such as a programmable gate array. Inanother example, the control module 150 may be implemented as controlmodule 150-2, which is implemented as computer program code 153 and isexecuted by the one or more processors 152. For instance, the one ormore memories 155 and the computer program code 153 are configured to,with the one or more processors 152, cause the SS 170 to perform one ormore of the operations as described herein.

The computer readable memories 125 and 155 may be of any type suitableto the local technical environment and may be implemented using anysuitable data storage technology, such as semiconductor-based memorydevices, flash memory, firmware, magnetic memory devices and systems,optical memory devices and systems, fixed memory and removable memory.The computer readable memories 125 and 155 may be means for performingstorage functions. The processors 120 and 152 may be of any typesuitable to the local technical environment, and may include one or moreof general-purpose computers, special purpose computers,microprocessors, digital signal processors (DSPs) and processors basedon a multi-core processor architecture, as non-limiting examples. Theprocessors 120, and 152 may be means for performing functions, such ascontrolling the UE 110, SS 170, and other functions as described herein.

In general, the various embodiments of the user equipment 110 caninclude, but are not limited to, cellular telephones (such as smartphones, mobile phones, cellular phones, voice over Internet Protocol(IP) (VoIP) phones, and/or wireless local loop phones), tablets,portable computers, vehicles or vehicle-mounted devices for, e.g.,wireless V2X (vehicle-to-everything) communication, image capturedevices such as digital cameras, gaming devices, music storage andplayback appliances, Internet appliances (including Internet of Things,IoT, devices), IoT devices with sensors and/or actuators for, e.g.,automation applications, as well as portable units or terminals thatincorporate combinations of such functions, laptop-embedded equipment(LEE), laptop-mounted equipment (LME), Universal Serial Bus (USB)dongles, smart devices, wireless customer-premises equipment (CPE), anInternet of Things (IoT) device, a watch or other wearable, ahead-mounted display (HMD), a vehicle, a drone, a medical device andapplications (e.g., remote surgery), an industrial device andapplications (e.g., a robot and/or other wireless devices operating inan industrial and/or an automated processing chain contexts), a consumerelectronics device, a device operating on commercial and/or industrialwireless networks, and the like. That is, the UE 110 could be any enddevice that may be capable of wireless communication. By way of examplerather than limitation, the UE may also be referred to as acommunication device, terminal device (MT), a Subscriber Station, aPortable Subscriber Station, a Mobile Station (MS), or an AccessTerminal.

Having thus introduced one suitable but non-limiting technical contextfor the practice of the exemplary embodiments, the exemplary embodimentswill now be described with greater specificity.

II. Examples related to interfaces for testing of SDT transmission inthe RRC inactive mode

This section relates to interfaces for testing of SDT transmission inthe RRC inactive mode. Much of this section may also have bearing onsection III, described below.

Before proceeding with additional description, it is noted that modes ofa UE, such as a connected mode or inactive mode are described herein.These modes may also be referred to as states. Further, the modes ormessages may be capitalized, in all capitals, or have other minordifferences in font. For example, RRC_CONNECTED, RRC_Connected, and RRCconnected are all considered to be the same mode. Furthermore, the namesof these modes include the RRC inactive state, RRC idle state, and theRRC connected state. It is possible these may be referred to bydifferent names, but the idle state is a power-saving state where datais not exchanged, the connected state is a state where datatransmissions occur, and the inactive state is another power-savingstate, but one where the UE is able to return quickly to the connectedstate.

II.a. Introduction of the Technical Area

This section provides an introduction of the technical area. Aspreviously described, in order for the CG-SDT to function properly,there is a mechanism for the UE to keep synchronicity in UL (uplink,from the UE to the network). While in RRC connected mode, the gNB (abase station providing access by the UE to the network) is able to alignthe UL transmissions though timing advance commands, TACs. However, whenthe UE is moved to the RRC inactive mode, there are no means for the gNBto keep this message exchange and keep the UL transmissions synchronousto the UL resources. Therefore, as part of the CG-SDT work, a TAvalidation mechanism is defined as part of RAN2 and RAN4 (see 3GPP TS38.133 clause 5.5). This validation basically is responsible to detectif the UE has moved, since a large UE movement would imply in adifferent propagation delay.

The TA validation procedure for CG-SDT works as follows. Two RSRP valuesare collected by the UE, as follows: RSRP1 is collected next to the timewhen the TAC is received by the UE; and RSRP2 is collected at the momentwhen the TA validation is performed for transmitting in a CG-SDToccasion.

While the UE is still in the RRC connected mode, in response to the UEreceiving a TAC command at time T1, the UE should make also an RSRPmeasurement, RSRP1 at time T1′. This measurement RSRP1 is consideredvalid for the purpose of CG-SDT only if |T1−T1′|<W1, where W1 is thewindow where the first RSRP value should be collected. The UE goes intothe RRC inactive mode when the UE receives an RRC Release with a suspendmessage from the gNB, and the UE may use SDT resources if this messageincludes the SDT configuration. In order for the UE to transmit in aCG-SDT resource, the UE should measure RSRP2 at time T2′, so that the UEcan make a decision to transmit on CG-SDT at time T2, whereT2−W2<T2′<T2, and W2 is the window where the RSRP2 should be measured.Additionally, there might be a limit Z on the time T3 of thetransmission on the CG-SDT resource and the time T2 as T3-T2<Z. The UEmay transmit on the CG-SDT occasion if the UE has valid RSRP1 and RSRP2measurements and if |RSRP1−RSRP2|<cg-SDT-RSRP-ChangeThreshold.

Once the UE meets these requirements, the UE should be able to transmitwith a small UL timing error on a CG-SDT occasion. This transmissionalso has requirements for the timing accuracy, as described in section7.1.2 of 3GPP TS 38.133.

Concerning an UL timing test case, existing UL timing accuracy (Te)requirements are tested in the appendix sections of 3GPP TS 38.133 forUEs while in RRC connected mode. One example is the test for Standalonein FR2, which is defined in clause A.7.4.1. In this clause, a system isconfigured with 240 kHz SSB, which has a periodicity of 20 ms, and 120kHz SCS transmission in UL. The test is conducted in RRC_CONNECTEDstate. The test is composed of the following steps, as illustrated byFIG. 2 , which is a signaling diagram illustrating a procedure forverification of the UL timing requirements of a UE:

1. A single NR PCell is configured by the TE (test equipment) 170 andused. In this example, a UE is illustrated by the DUT, device undertest, 110.

2. After connection setup, the test equipment verifies whether theinitial transmission timing error is within ±Te based on the SRS signaltransmitted from the UE under test (and the corresponding SSBtransmitted by the SS 170). See block 230, where |UL error|<T_(e).

3. The system simulator adjusts the timing of the DL path by a constantshift. See block 240.

4. The test equipment verifies again that the UE is able to adjust itstransmit timing so that the transmit timing error is within ±Te whilefollowing the adjustment step size and the adjustment rate requirementsof clause 7.1.2.1 of 3GPP TS 38.133. See block 250, where the SS 170monitors if the UE can adapt to the new DL timing and also block 260,where the SS monitors if the transmit timing error is within ±Te. Thisis illustrated by |UL error|<T_(e).

Example test methodology is now described. While testing devices, thebest technique is to test the device as a black box, and the most commonuse case is having the device connected to a network simulator (SS 170)via the air interface only. However, this is not possible in all usecases. For example, when testing data transfer, it is important for thenetwork simulator to be able to trigger transmissions and to havecontrol of what the device is sending. In the example above, the SS doesnot have to trigger data transmissions from the UE, since the SSconfigures SRS and is able to perform the test based on referencesignals such as SRS. The same is not possible for SDT tests, since theSDT messages should contain data to be sent while in RRC inactive mode,and not pure reference signals as in the UL timing test case.

For such a case, specific Over The Air Test commands, OTA TST commands,are used. The test commands have their own protocoldiscriminator/protocol end point, a protocol running in parallel toother protocols at layer 3 level, like RRC, MM, and the like. The testcommands are specified in 3GPP TS 38.509 for NR, and in 3GPP TS 36.509for LTE.

One set of commands is for loop back of data, meaning the networksimulator sends data towards the device and the device is configured tosend the same frames back in the uplink. The mapping between downlinkand uplink and at which protocol layer loopback is performed, can beconfigured. The general principle is shown in FIG. 3 , which is asignaling diagram illustrating OTA TST command for test loops. The UE isin the RRC_Connected state in block 330, and the SS (system simulator)170 signals the UE 110 to close the UE test loop. The UE 110 thenindicates back to the SS 170 that the close UE test loop is complete viasignaling.

Another way to control the device is via MT/Terminal Equipmentcommunication as suggested in 3GPP TS 27.007. This requires a physicalinterface separate to the 3GPP air interface which allows the exchangeof AT (ATtention) commands. In this way, it is possible to command andcontrol test procedures in the device. An example is for V2X testing,which is given in section 15 of 3GPP TS 27.007.

Various test modes and test commands are defined in 3GPP TS 36.509 and3GPP TS 38.509. Test loops generally require that the PDUs to loopbackare transmitted by the system tester in the downlink. One of the definedtest loop modes is called “UE test loop mode B” and allows setting atimer (e.g., using an integer number of seconds) so that the UE loopsback the data in the UL after the timer has expired. This allows delayin the loopback function, which could be useful for basic SDT testing.However, this mode is very limited in timer granularity, and there is nocontrol of when and how much of the buffered data are scheduled forloopback. It is a “one-shot” solution, where the only possible method isto loopback all the buffered data, and further uplink can only bescheduled upon reception of new downlink data by the UE.

AT commands are also used to control UE behavior during testing.Standardized AT commands are defined in 3GPP TS 27.007, but devicestypically also support proprietary commands or extensions. The ATcommand +CCUTLE is currently defined in 3GPP TS 38.509, clause 5.3.2.2,and this is pending to be added to 3GPP TS 27.007. This command can beused for NR Sidelink to (among other things) trigger transmission by theUE being tested, after the test loop has previously been closed.However, no specific timing on when the transmission takes place can beindicated.

II.b. Exemplary Embodiments for Testing of SDT Transmission in the RRCInactive Mode

These and other issues may be addressed by the exemplary embodimentsherein. Examples here enable methods to force the use of SDT fortesting, with options to repeat as many times as needed to verify thedevice without excessive signaling. This will provide the ability totest one or more of the following:

-   -   1) Any part of the SDT features, protocols, the SDT decision        tree, i.e., verify which SDT procedure that is used, and the        like;    -   2) The TA validation procedure; and/or    -   3) The timing of uplink transmissions.

Three exemplary methods are suggested, as follows.

-   -   1. Method 1: A pure loopback mode, where the TST CMD configures        everything in relation to what to send and when, see FIG. 4 .    -   2. Method 2: A combination of TST CMD configuration and AT        commands to configure and trigger an SDT procedure, see FIG. 5 .    -   3. Method 3: A pure AT command-based procedure, where the AT        command provides the data frames to send as well as timing of        the SDT procedure, see FIG. 6 .

With these methods, test data package(s) may be communicated from the SS170 to the UE 110, and the test data package(s) are transmitted by theUE according to the configured test method that defines thecommunication sequence to be performed. The UE performs communication asindicated by the SS in order to perform the test(s), and the SS monitorsthe UE behavior and reports the results. In further detail, the testdata packages define (e.g., potentially include) the data that the UEshould transmit, and the sequence to be performed to transmit the datais configured with, e.g., a test loop mode command or AT command.

These exemplary methods are now described.

In the example Method 1 shown in FIG. 4 , a loopback implementation isproposed. As part of this implementation, the SS indicates that the UEshould send SDT messages at a given time configured by the SS. Block 410indicates that the test step starts, by getting the UE 110 to transmitone SDT session. The main steps that are involved in the loopbackcommunication can be described as follows.

Step 1. First, activate test mode. See block 420.

1.a. The SS 170 has to send an ACTIVATE TEST MODE message indicatingthis activation. This message is sent over the air while the UE is RRCconnected mode (see block 415).

1.b. This step enables the DUT (UE 110) to start to receive testcommands, and the UE responds with an ACTIVATE TEST MODE COMPLETEmessage. In these examples, the UE 110 is considered to be the DUT.

Step 2. Close UE test loop, as indicated by block 425.

2.a. In this step (close UE test loop), the SS 170 indicates to the DUT170 the test mode that is used for sending SDT in UL while the UE is inRRC inactive mode.

2.b. As part of the message sent to the DUT, the message may include(see reference 426):

2.b.i. Indication of the test mode using small data transmission (SDT);

2.b.ii. Indication of the time when SDT messages (e.g., a firsttransmission of these) should be sent in UL.

2.b.iii. Indication on the number (N) of repetitions that the SDTpackage should be transmitted. One value can be used to indicate the UEthat the repetitions should take place as long as the UE is RRCinactive, or that the UE TEST LOOP is still activated.

2.b.iv. Indication on the time period between the repetitions.

2.c. The UE responds with a “close UE test loop complete” message.

Step 3. PDSCH data transmission.

3.a. In this step, the SS sends a PDSCH with test data package(s) 421-1that include the payload that should be used by the UE (see signaling427).

Step 4. Move the UE to the RRC inactive state (see block 430).

4.a. This step is accomplished by the SS by sending a RRC release withsuspend to the UE. See signaling 428, including RRC release w/ suspendconfiguration containing CG-SDT and RA-SDT configuration (config.)including (incl.) TimeAlignmentTimer).

4.b. With this message, the UE transitions to the RRC inactive state(see block 430), and receives the configuration for SDT.

Step 5. At the time configured in the “Close UE test loop” step, thefollowing occurs. The time is indicated by block 435.

5.a. The UE is expected to initiate a SDT transmission.

5.b. If the transmit power used by the SS allows for CG-SDTtransmission, i.e., the measured RSRP value by the UE meets the TAvalidation criteria, the UE will transmit the payload, received in PDSCHduring step 3 and defined by the test data package(s) 421-1, usingCG-SDT (as per block 435), otherwise the UE will use RA-SDT. This isindicated by block 445, the signaling 446 (“CG-SDT Txm (transmission)carrying UL MAC PDU incl RRC Resume Request+UL payload”), and signaling447 (the “CG-SDT Txm complete carrying DL MAC PDU incl RRC Release w/Suspend indication”). After this, the UE moves into the RRC_Inactivemode (see block 450). Note that there is a decision tree 461 that may beused to determine what type of SDT to perform based on differentparameters. It is not a given that RA-SDT is allowed. This is explainedbelow in reference to FIG. 4A.

5.c. This step is repeated N times (see block 451) with the periodicityconfigured in step 2.

Step 6. The SS 170 pages the UE 110. See signaling 451 (“Paging toresume RRC connected mode”).

6.a. This step is used for the UE to come back into RRC connected state(see block 455), and enable further loopback commands.

Step 7. Conclusion of the testing mode.

7.a. The UE is in the RRC_Connected mode 455 after the paging, and theSS 170 sends an OPEN UE TEST LOOP message, which deactivates the testloop. The UE responds with an OPEN UE TEST LOOP COMPLETE message.

7.b. The SS sends a DEACTIVATE TEST MODE message, after which the UEdeactivates the test mode and returns to normal operation. The UEresponds with a DEACTIVATE TEST MODE COMPLETE message.

The test step is now complete. See block 460.

Turning to FIG. 4A, this figure is a logic flow diagram illustrating aflowchart for a decision tree 461 on what SDT procedure, if any, toperform based on different parameters, in accordance with an exemplaryembodiment. This logic flow diagram is performed by the UE 110. The flowis broadly viewed as three selection steps (a general SDT selection step465, a CG-SDT selection step 470, and an RA-SDT type selection step 480)and a non-SDT selection (step 492).

The flow starts in block 462, where UL data is on SDT DRB(s). The SDTselection step 465 selects whether or not SDT will be performed. Inblock 466, it is determined whether data volume meets a threshold (inthis example, is ≤SDT data volume threshold). If not (block 466=no), theflow proceeds to step 492, where a non-SDT procedure is performed. If so(block 466=yes), in block 468 the UE determines whether RSRP meets athreshold (i.e., is ≥SDT RSRP threshold in this example). If not (block468=no), the flow proceeds to block 492. If so (block 468=yes), the flowproceeds to the CG-SDT selection step 470, which determines whetherCG-SDT will be performed.

In CG-SDT selection step 470, in block 472, the UE determines whether CGresources are configured. If not (472=no), the flow proceeds to RA-SDTtype selection step 480, which selects the type of RA-SDT procedure. Ifso (block 472=yes), the UE determines whether CG resources are availableand a TA timer is not expired, and an RSRP change is within a threshold.If so (block 474=yes), the UE determines whether any SSB meets athreshold (e.g., is above an SS-RSRP threshold) and if so, the UEperforms a CG-SDT procedure and the flow ends. If either block 474 or476 are no, the flow proceeds to 480.

In the RA-SDT type selection step 480, the first block is block 482,where the UE determines whether 2 step RA-SDT resources are available.If so, the UE determines in block 484 whether an RSRP>SDT MsgA RSRPthreshold in block 484. If so, the UE performs a 2-step RA-SDT procedurein block 478 and the flow ends.

If either block 482 or 484 is no, the flow proceeds to block 488, wherethe UE determines whether 4 step RA-SDT resources are available. If so,the UE performs a 4-step RA-SDT procedure in block 480, and the flowends. If block 488 is no, the flow proceeds to block 492.

Exemplary differences between existing test loops (for example, loopmode B) and this one includes the ability to give an exact occasion forwhen the SDT session should be triggered and the ability to configurehow much of the data that should be forwarded from the test function tothe lower layers per SDT session. In this way, frames can be stored forlater transmission over several SDT sessions without having to send datato the device during the test session, and all is handled in connectedmode before the actual testing starts. The existing loopback messageexchange is also currently performed only in RRC connected, so thisimplies that the SS and DUT can only communicate while the UE is in RRCconnected. With Method 1, this limitation is overcome, since theloopback commands are indicating the actions that the DUT have toperform after it moves to RRC inactive.

Additionally, with this example, the same data can be used for every SDTsession, meaning, if the purpose of the test is to verify the UEdecisions for each of the SDT sessions, the actual data is indifferent.Therefore, the test loop command with a new loop type could store afixed set of data used for every SDT session in the test. This is aclear advantage, since if repetitions were not allowed, the UE wouldneed to transition to RRC connected before every new SDT transmission,and the testing time would be significantly increased or the devicewould need to store a larger amount of data during RRC inactive mode forlater SDT transmission. Another method is to send data on the fly bygiving the data to be transmitted in the downlink before or as part ofthe data holding the RRC release. This is not considered optimal, as itmay violates the black box testing concept, and is therefore notconsidered further herein.

An alternative solution using loopback commands and AT commands isproposed in Method 2 and shown in FIG. 5 . The solution in Method 2 hassimilar advantages as to the advantages of Method 1, but Method 2 solvesthe problems differently. The data used for SDT sessions is stilltransferred in loop back mode prior to the test execution, however thedata is then triggered for SDT sessions using an AT command. The ATcommand itself can, besides number of SDT sessions, also be specified tohold timing information on the SDT sessions themselves as in theprevious solution. One advantage of this solution in comparison to themethod 1 is that it enables more flexible triggering of the SDTmessages. It is noted that the command +CSDT is just an example name ofa potential new AT command for this purpose, and other names or commandsmight be used.

In the Method 2 shown in FIG. 5 , a combination of loopback and ATcommands is proposed. The main steps that are involved in thisalternative method are described as follows. Many of these steps orsignaling have already been described with respect to FIG. 4 . Block 410indicates that the test step starts, by getting the UE 110 to transmitone SDT session.

Step 1. First, activate test mode. See block 420.

1.a. The SS 170 has to send an ACTIVATE TEST MODE loopback messageindicating this activation. This message is sent over the air while theUE is RRC connected mode (see block 430).

1.b. This step enables the DUT (UE 110) to start to receive testcommands, and the UE responds with an ACTIVATE TEST MODE COMPLETEmessage. In these examples, the UE 110 is considered to be the DUT.

Step 2. Close UE test loop, as indicated by signaling 505.

2.a. In this step (close UE test loop), the SS 170 indicates to the DUT170 the test mode that is used for sending SDT in UL while in RRCinactive.

2.b. As part of the message sent to the DUT 110, the message may includethe following.

2.b.i. Indication of the test mode using small data transmission. Thatis, existing test loop mode messages indicate which test mode is beingconfigured at the UE, such as Test Loop Mode A, B, C, and the like forvarious purposes. This indication refers to a new extension to thatmessage to configure this new proposed test mode.

2.b.ii. In one implementation option, the SS indicates the timing of theSDT transmissions in relation to the AT command of step 5 (describedbelow). In another implementation option, the timing is indicated in theAT command of step 5.

2.c. The UE response with a CLOSE UE TEST LOOP COMPLETE message.

Step 3. PDSCH data transmission.

3.a. In this step, the SS sends a PDSCH with the test data package(s)421 with payload(s) that should be used by the UE (see signaling 510,“PDSCH with test data package(s)”) for testing.

Step 4. Move the UE to the RRC inactive state.

4.a. This step is accomplished by the SS by sending an RRC release withsuspend to the UE. See signaling 515, “RRC Release w/ Suspend Configcontaining CG-SDT Configuration incl. TimeAlignmentTimer”.

4.b. With this message, the UE transitions to the RRC inactive state(see block 430), and receives the configuration for SDT.

Step 5. The SS sends AT command to initiate SDT communication.

5.a. This AT command triggers the UE to start transmitting using SDT. Inthe example, the AT command triggers 2 SDT transmissions, one after theother. The triggering of the 2 SDT transmissions (see 440-1 and 440-2)via the AT command is indicated by the “AT+CSDT 2” in signaling 540. Itis noted that the decision tree of FIG. 4A may also be used, in order toselect the SDT type. This example has a single AT command (in signaling540) that triggers multiple transmissions, in this case twotransmissions 446-1 and 446-2. That is, multiple transmissions 446 maybe triggered by a single AT command.

5.b. In one implementation option, the SS indicates in step 2 (e.g.,blocks 425, 505) the timing of the SDT transmissions in relation to theAT command. In another implementation option, the timing is indicated aspart of the AT command (e.g., in block 535 and signaling 540).

5.c. If the transmit power used by the SS allows for CG-SDTtransmission, the UE will transmit the payload sent in PDSCH during step3 using CG-SDT, otherwise the UE will use RA-SDT if the related criteriaallow for it. The SS may also not configure RA-SDT resources forcing theUE to use only CG-SDT resources and vice versa. This is indicated byblock 445 (“Payload is what was previously received on PDSCH after thetest loop was closed”), signaling 446 (“CG-SDT Txm (transmission)carrying UL MAC PDU incl RRC Resume Request+UL payload”), and signaling447 (“CG-SDT Txm complete carrying DL MAC PDU incl RRC Release w/Suspend indication”). Note that the payload is what was defined by(e.g., included in) the test package(s) 421-2.

5.d. This procedure may be repeated as long as the UE is in RRC inactivestate (see block 450). That is, the AT command (from signaling 540) maybe transmitted multiple times as long as the UE is in RRC inactivestate. In this example, there are multiple blocks 430, 550, and 450,which indicate the UE is in RRC_INACTIVE mode, and these are to clarifythat the UE stays in this state for this example.

Step 6. The SS pages the UE.

6.a. This step is used for the UE to come back into RRC connected mode(see block 455), and enable further loopback commands See signaling 451(“Paging to resume RRC connected mode”).

Step 7. Conclusion of the testing mode.

7.a. The UE is in the RRC_Connected mode (see block 455) after thepaging, and the SS 170 sends an OPEN UE TEST LOOP message, whichdeactivates the test loop. The UE responds with an OPEN UE TEST LOOPCOMPLETE message.

7.b. The SS sends a DEACTIVATE TEST MODE message, after which the UEdeactivates the test mode and returns to normal operation. The UEresponds with a DEACTIVATE TEST MODE COMPLETE message.

The test step is now complete. See block 460.

Another example is illustrated as Method 3, which is shown in FIG. 6 andhas the same advantages as previously mentioned for Methods 1 and 2, butdoes further have the advantage of not having to store any loop-backdata. Instead, the data is generated on the fly by (e.g., a test entityin) the UE. In this example, the AT command is specified to provide anumber of SDT sessions to be triggered, the format of the data sent andlast the number of bytes in the transmission. The main steps that areinvolved in this alternative method are described as follows. Many ofthe steps and signaling in FIG. 6 are similar to what was in FIGS. 4 and5 . Block 410 indicates that the test step starts, by getting the UE 110to transmit one SDT session.

In this example, there may no loop. Instead, the data to send in SDT isnot a loop back of data receive OTA, but a transmission of dataspecified by the AT command itself, i.e., in this example, (e.g., thetest entity of) the UE generates the data itself. The data could also beprovided in the AT command itself. Additionally, test mode may not beactivation, though it still may make sense to activate test mode, e.g.,so as to allow the AT commands in the UE.

Step 1. First, (optionally) activate test mode. See block 420.

1.a. The SS 170 has to send an ACTIVATE TEST MODE loopback messageindicating this activation. This message is sent over the air while theUE is RRC connected mode (see block 415).

1.b. This step enables the DUT (UE 110) to start to receive testcommands, and the UE responds with an ACTIVATE TEST MODE COMPLETEmessage. In these examples, the UE 110 is considered to be the DUT.

Step 2. Move the UE to the RRC inactive state.

2.a. This step is accomplished by the SS 170 by sending an RRC releasewith suspend to the UE. See signaling 515, where the SS 170 sends an RRCRelease with (w/) Suspend Configuration (Config) containing CG-SDTConfiguration (Config) including (incl.) TimeAlignmentTimer.

2.b. With this message, the UE transitions to the RRC inactive state(see block 430), and receives the configuration for SDT.

Step 3. SS sends AT command to initiate SDT communication.

3.a. This AT command (see block 635) triggers the UE to starttransmitting using SDT (see block 635, “AT command to trigger 1 SDTsession), and may include a predefined SDT test package 421-3 (see block635, “with data format 3, 42 bytes”), and signaling 637, “AT+CSDT 1, 3,42”), comprising:

3.a.i. Data format (e.g., data format 3 in this example);

3.a.ii. Payload to be generated (e.g., 42 bytes in this example); and/or

3.a.iii. Number of SDT sessions (e.g., one CSDT session indicated).

3.b. If the transmit power used by the SS allows for SDT transmission,according to the SDT decision tree (see FIG. 4A) and TA validationcriteria, the UE will perform the following (see block 645, “Payload isthe specified format 3 frame with 42 bytes of payload”):

3.b.i. Generate a random payload with the number of bits configured inthe AT command, where in this case the payload is defined by the testdata package 421-3;

3.b.ii. Transmit the payload via CG-SDT or RA-SDT (see, for thisexample, signaling 446 (“CG-SDT Txm carrying UL MAC PDU incl RRC ResumeRequest+UL payload”), and also the response from the SS in signaling 447(of “CG-SDT Txm complete carrying DL MAC PDU incl RRC Release w/ Suspendindication”);

3.b.iii. Transmit again the payload for the repetitions configured inthe AT command See reference 451 (e.g., Repeat N times).

3.c. The system simulator may initiate this procedure again as long asthe UE is in test mode an in the RRC inactive state and initiated bysending a new AT command.

The UE remains in the RRC_INACTIVE mode. The blocks 430 and 450 are usedto illustrate the UE is still in RRC inactive between 446 and 447, andto make it clear that the UE has not changed state. In other non-SDTcontexts, the UE could send an RRC resume request to ask to be againplaced into RRC connected, but this is not the case in this figure.

Step 4. SS moves the UE to RRC connected.

4.a. SS sends a paging message to the UE (see signaling 451, “Paging toresume RRC connected mode”). This step is used for the UE to come backinto the RRC connected mode (see block 455, “UE in connected mode”), andenable further loopback commands.

5. Conclusion of the testing mode.

5.a. The SS sends a DEACTIVATE TEST MODE message, after which the UEdeactivates the test mode and returns to normal operation (and sends aDEACTIVATE TEST MODE COMPLETE message).

At this point, the test step is complete (see block 460).

When compared to Methods 1 and 2, the Method 3 has an advantage becausethis method does not require the SS to send PDSCH containing the payloadto be transmitted by the UE. Additionally, since the AT command wouldinclude the payload size, multiple SDT sessions could be triggered withdifferent sizes without the need to move the UE to RRC connected mode.That would imply a faster test procedure in case many test cases thatare concatenated (as it is time consuming for a UE to move to RRCconnected mode). For example, this enables the SS to verify if the UEcorrectly moves to RRC connected in case the amount of data to transmitexceeds the maximum threshold for SDT transmissions.

An advantage of Method 1, compared to Methods 2 and 3, is that thesystem simulator 170 does not need a second interface to the UE;instead, the SS 170 only needs the air interface that is under testanyway.

Any of the above solutions could be extended to allow the triggering ofsub-sequent SDT transmissions—SDT sessions with more uplinktransmissions than one.

Lastly, it should be noted that the examples all show CG-SDT sessions,but the examples can also force the choice between CG-SDT and RA-SDTtransmissions if not given by the channel configuration itself in thetest. For example, to test the device correctly choose between CG-SDTand RA-SDT sessions.

Without in any way limiting the scope, interpretation, or application ofthe claims appearing below, a technical effect and advantage of one ormore of the example embodiments disclosed herein is enablement of easyverification of the CG-SDT functionality through loopback or AT commandinterfaces. Another technical effect of one or more of the exampleembodiments disclosed herein is new testing mode commands that cancontrol the UE behavior also when the UE is in RRC inactive or RRC idleis developed, and a provision of a good level of control for the SS onwhen the CG-SDT transmissions are triggered.

III. Examples Related to Testing Methods for Verification of TAValidation of CG-SDT

This section relates to testing methods for verification of TAvalidation of CG-SDT.

III.a. Introduction of the Technical Area

In addition to the introduction in II.a. above, this section providesadditional introduction specific to this testing methods forverification of TA validation of CG-SDT. Turning to FIG. 7 , split intoFIG. 7A and FIG. 7B, this figure illustrates diagrams showing testingmethod used for random access procedures. FIG. 7A illustrates a Test 1and FIG. 7B illustrates a Test 2. FIG. 7 illustrates an example ofanother RRM test case. In this example, the UE is triggered to sendPRACH preambles while in RRC connected mode. Two variants of this testare specified. In Test 1 (FIG. 7A), the behavior after receiving arandom-access response RAR with no matching RNTI is evaluated, while inTest 2 (FIG. 7B), the behavior of the UE that does not receive any RARis evaluated.

As indicated in FIG. 7A, the UE 110 performs a PRACH procedure, and thetest equipment, e.g., a gNB, 170 verifies Tx power and timing. Thefollowing are repeated four times: The SS 170 sends an RAR not matchingRA-RNTI, the UE 110 performs power ramping and then performs anotherPRACH procedure, and the SS 170 again verifies UE Tx power and timing.The SS 170 sends another RAR, this time matching RA-RNTI msg3 grant, andthe UE responds with Msg3.

FIG. 7B is similar to FIG. 7A, and differences are mainly described. Forthe repetition part, the UE has a random backoff that expires, then theUE performs power ramping.

In both cases, after each PRACH transmission the SS verifies thetransmit power and timing accuracy.

There are challenges on how TA validation procedure can be verified bytest cases. The existing RRM test cases rely mostly on random-accessmessages, and dynamic grants, but none of the existing RRM test casesspecified in 3GPP TS 38.133 include configured grants.

In order to ensure good quality commercial deployment of the SDTfeature, it is important that conformance tests are able to verify thefollowing aspects:

-   -   1) Verify that the UE respects the windows where the        measurements should be performed.    -   2) Verify that CG-SDT transmissions are only performed when the        TA validation conditions allow for the transmissions.    -   3) Verify that CG-SDT transmissions do not exceed the maximum UL        timing accuracy.

In order to achieve the above aspects, solutions should be found for atest equipment SS and a UE in that enables the verification that theconditions for CG-SDT hold and transmissions are with the specifiedaccuracy.

III.b. Examples for Testing Methods for Verification of TA Validation ofCG-SDT

The examples herein describe a test method which is used to verify thebehavior of UEs using CG-SDT. CG-SDT uses two RSRP windows, from whichthe RSRP levels are compared in order to determine if the UE is allowedto transmit in CG-SDT. Considering that scenario, a test method isdeveloped that verifies if the UE is indeed obtaining RSRP values withinthe specified windows.

In order to achieve that objective, the test equipment changes thetransmit power in the times when the UE was following the requirementsfor TA validation. Refer to FIG. 9 , which illustrates test equipmentpower relative to the TA validation conditions when considering P₁,power applied during the first RSRP measurement window, P₀, and the SSpower during RRC connected mode outside of the first RSRP window. Thetest starts with a power level P₀, which is changed to P₁ during themeasurement window which should be used by the UE for measuring RSRP1.The SS power is changed back to P₀. It is noted that a measurementwindow is a time period during which a measurement is (or measurementsare) expected to be performed.

As a second step, the test equipment moves the UE to RRC inactive, andchanges the power levels to values during predefined time intervals suchthat one of the following conditions are met:

-   -   1) Condition 1: The TA validation condition is satisfied, i.e.        the SS transmit power in the second RSRP window P is such that        |P₁−P|<cg-SDT-ChangeThreshold, and CG-SDT is allowed.    -   2) Condition 2: The TA validation condition is not satisfied,        i.e. the SS transmit power in the second RSRP window P is such        that |P₁−P|>cg-SDT-ChangeThreshold, and CG-SDT is NOT allowed.    -   3) Condition 3: The TA validation condition is not satisfied,        i.e. the SS transmit power in the second RSRP window P is such        that |P₁−P|>cg-SDT-ChangeThreshold, and CG-SDT is NOT allowed,        and P is chosen such that if RSRP1 is measured outside of the        window the TA validation condition would be satisfied, i.e.,        |P₀−P|<cg-SDT-ChangeThreshold. This step is used to verify if        the UE measured RSRP1 outside the measurement window.    -   4) Condition 4: The TA validation condition is not satisfied        and, i.e., the SS transmit power in the second RSRP window P is        such that |P₁−P|>cg-SDT-ChangeThreshold, and CG-SDT is NOT        allowed. Additionally, the SS transmit power before Px the start        of the RSRP2 measurement window is chosen such that        |P₁−Px|<cg-SDT-ChangeThreshold. This condition is used to verify        if the UE has measured RSRP2 outside the measurement window.

The SS-transmitted values for Condition 1 are used to verify if the UEis able to transmit on CG-SDT when the TA validation is valid. Duringtimes when Condition 1 is valid, the SS verifies that the UE istransmitting CG-SDT. During times when Condition 2 is valid, the SSverifies that no transmission of CG-SDT is performed by the UE, and ifthe UE transmits a CG-SDT the UE has failed the test. Condition 3includes an additional check in relation to Condition 2, which verifiesif the first RSRP measurement was obtained inside the correctmeasurement window by the UE. Likewise, Condition 4 includes anadditional chek in comparison to condition 2, which verifies if thesecond RSRP measurement was obtained inside the correct measurementwindow by the UE. Please notice that the combination of these conditionsduring the test procedure allow the system simulator to identify if theUE has performed the correct measurement, if the measurements werecollected at the correct measurement windows, and it would verify if theUE only sends CG-SDT when the UE is allowed to do so.

FIG. 8 , which is spread over FIGS. 8A and 8B, is a sequence diagramdescribing the test case steps for verification of TA validation ofCG-SDT in an exemplary embodiment This figure shows the steps involvedin the CG-SDT testing considering power levels P₀, P₁, P₂, and P₃. Anexample for possible power values for P₀, . . . , P₃ is shown in FIG. 9.It is noted that the decision tree of FIG. 4A may also be used, in orderto select the SDT type. Additionally, this figure is assumed to be anadjunct to other figures, thereby combining the methods for transmittedpayloads would be defined either in FIG. 4, 5 or 6 . That is, it isexpected that FIG. 4, 5 or 6 are used to configure the UE to startsending SDT transmissions, and in FIG. 8 the testing steps are verified.That means, if one uses Method 1 (FIG. 4 ), the SS would activate thetest mode, close the test loop, and send the test data package to beused by the UE. After that the UE would be expected to send SDT packagesas in FIG. 8 . For ease of reference, FIG. 4 is assumed to be combinedwith the techniques of FIG. 8 , but the configuring performed in FIG. 5or 6 might be used instead.

The steps can be further described as follows, illustrated in FIG. 8 .

Step 1: The test starts with the UE in RRC connected mode (block 903),and with the SS 170 setting (block 905) a power level of P₀. Reference908 indicates examples of configuring that can be performed from FIG. 4. See FIG. 4 for more details.

Step 2: At time t=T_(A) the SS 170 sets (block 910) the power level toP₁. P₁ is chosen as |P₀−P₁|>cg-SDT-ChangeThreshold.

Step 3: The SS 170 sends a TAC at time t=T_(B)≥T_(A)+W_(RSRP1). This isindicated by the signaling 915, “MAC CE TA command” at t=T_(B).

Step 4: At time t=T_(C) the SS 170 sets (block 920) the power level toP₀.

a. T_(A), T_(B) and T_(C) are chosen via the following:T_(B)=T_(A)+W_(RSRP1)+W_(REP)−ε_(B), andT_(C)=T_(B)+W_(RSRP1)+W_(REP)+ε_(C), where W_(RSRP1) is the window tomeasure the first RSRP value, W_(REP) accounts for the measurementrepetitions needed for the measurement of the RSRP, and ε_(B) and ε_(C)should be close to zero and are used to consider limitations on when theTAC may be sent and power can be changed by the test equipment.

Step 5: At time t=T_(D), the SS 170 sends (signaling 925) an RRC releasewith suspend message to the UE including the SDT configuration. TheCondition 3 is used between T_(D) and TE, as described in more detail inreference to FIG. 9 .

a. In response to this message, the UE goes to the RRC inactive mode(block 930). CG-SDT are still not allowed, since the SS power willresult in an RSRP variation above the cg-SDT-ChangeThreshold, i.e.,|P₀−P₁|>cg-SDT-ChangeThreshold. At this time, if the UE transmitsCG-SDT, the test run is considered as failed.

Step 6: At time t=TE, the SS 170 then sets (block 935) the transmitpower as P₂ and adjusts the DL transmit timing by T_(DELTA). P₂ ischosen such that the T_(A) validation conditions allow for a CG-SDTtransmission, i.e., |P₂−P₁|<cg-SDT-ChangeThreshold. T_(DELTA) is used toverify if the UE 110 is able to adapt to the DL timing during the CG-SDTtransmissions.

Step 7: The SS 170 should wait for N1 CG-SDT transmissions, which shouldoccur during the CG occasion 945. The Condition 1 is used between T_(D)and TE, as described in more detail in reference to FIG. 9 .

7.a. The SS should verify (block 955) that the CG-SDT transmissions(indicated by the signaling 940 from the UE 110 to the SS 170 with|P₁−P₂|<cg-SDT-ChangeThreshold) have a transmit power within the poweraccuracy, and that the UL transmit timing error is smaller than Te(e.g., as specified in section 7.1 of 3GPP TS 38.133). For the example,there is a CG-SDT transmission (TXm) carrying UL MAC PDU including(incl) RRC Resume Request and an UL payload (as described in more detailin reference to FIG. 4 ). This process is repeated N1 times, N1≥1, seeblock 950. The signaling 940 may be considered to be a test data packagetransmitted by the UE. At this time, if the UE transmits CG-SDT and thetransmit power or the transmit timing error exceed the limits describedabove the test run is considered as failed.

Step 8: At time t=T_(F) the SS 170 sets (block 960) the power to P₃. P₃is chosen as |P₁−P₃|>cg-SDT-ChangeThreshold, i.e., CG-SDT transmissionsare allowed since the UE should not pass the T_(A) validationrequirements. At this time, the testing condition 4 is met, which meansthat if the UE uses a measurement for RSRP2 outside the measurementwindow, the UE will transmit on CG-SDT occasion 975 and fail the test.Additionally, P₃ may be also be chosen as|P₀−P₃|<cg-SDT-ChangeThreshold. In this case, if the UE is measuring thefirst RSRP value outside of the valid measurement window, the UE wouldpotentially pass the T_(A) validation requirement and send CG-SDT (seecondition 3). The SS 170 should ignore CG-SDT transmissions (see block965) in the CG occasion for a time equivalent to W_(RSRP2)+Z+W_(REP),where W_(RSRP2) is the length of the second RSRP window (i.e., T_(F)RSRP2 window, as shown in signaling 970 in FIG. 8 ), Z is the timebetween the T_(A) validation decision and the CG-SDT occasion, andW_(REP) accounts for the measurement repetitions needed for themeasurement of the RSRP. The signaling 970 may be considered to be atest data package transmitted by the UE. For the example, there is aCG-SDT transmission (TXm) carrying UL MAC PDU including (incl) RRCResume Request and an UL payload (as described in more detail inreference to FIG. 4 ). These transmissions should be ignored (indicatedby “ignore transmissions”), since the UE might still have a validmeasurement on the second RSRP window that passes the T_(A) validationcriteria.

Step 9: After time t=T_(G) (block 980), CG-SDT transmissions are notallowed anymore. T_(G)=T_(F) W_(RSRP2)+Z+W_(REP). At this time, if theUE transmits CG-SDT, e.g., in CG occasion 990, the test run isconsidered as failed. This is indicated by the signaling 985, with|P₁−P_(s)|>cg-SDT-ChangeThreshold that ends with an “x”. The SS 170verifies (block 995) there are no CG-SDT transmissions. The time betweenT_(G) and the end of the test should be large enough such that itcontains N2≥1 CG-SDT occasions, as indicated by block 997.

It is noted that the threshold comparisons performed herein can becharacterized as meeting a threshold. As one example, the|P₀−P₃|<cg-SDT-ChangeThreshold comparison is used above. This may bemore broadly characterizes as the |P₀−P₃| meets a threshold, which isbeing less than cg-SDT-ChangeThreshold.

Turning to FIG. 9 , this figure illustrates an example of SS power overtime for the test procedure as used in FIG. 8 , in an exemplaryembodiment, and illustrates further the variation power levels thatshould be applied by the SS for each part of the test. In this figure,it is shown how the power levels after the UE is in RRC inactive mode inT_(D) are adjusted to fit the conditions described:

-   -   Condition 1: between TE and T_(F);    -   Condition 3: between T_(D) and TE;    -   Condition 4: between T_(G) and the end of the test;

Condition 2 is not used in this diagram since condition 3 and condition4 are strict and enough for the test coverage, but the same times usedfor condition 3 and condition 4 could apply for condition 2 as well.

As a reminder, for these examples, only for Condition 1, the T_(A)validation condition is satisfied, i.e., |P₁−P₂|<cg-SDT-ChangeThreshold,and CG-SDT is allowed; for Condition 3 and Condition 4 the T_(A)validation condition is not satisfied, i.e.,|P₁−P₀|>cg-SDT-ChangeThreshold, and CG-SDT is NOT allowed. Conditions 1,3, and 4 are indicated in FIG. 9 .

The TAC is sent by the SS 170 at time T_(B) is illustrated in FIG. 8 andFIG. 9 , which is centered at the first RSRP window, as is the RRCRelease w/ suspend at time T_(D), and the first CG-SDT transmission bythe UE (which occurs after T_(E)). FIG. 9 illustrates also the timeswhen the SS should ignore eventual CG-SDT transmissions between T_(F)and T_(G). Since the exact time when the UE performs the RSRPmeasurement is not mandated for the UEs, in this time interval there isa chance that the UE passes and fails the T_(A) validation criteria andstill conforms to the specification, therefore the SS 170 should allowfor transmissions in this time interval.

Without in any way limiting the scope, interpretation, or application ofthe claims appearing below, technical effects and advantage of one ormore of the example embodiments disclosed herein include the followingfor enabling verification of the T_(A) validation mechanism where:

-   -   1) SS transmit power levels are adjusted so that it is ensured        that the UE is using the correct procedure for T_(A) validation.    -   2) The power during RRC connected is set such that the transmit        power level during the first RSRP measurement window is set such        that if the UE measures outside this window, the UE will not be        able to transmit on the times it is expected to transmit in        CG-SDT while in RRC inactive mode;    -   3) The power while the UE is in RRC inactive is set such that    -   a) The UE will only be able to transmit in the correct CG-SDT        occasions if the UE has measured RSRP1 inside the measurement        window and RSRP2 inside the second RSRP window; and/or    -   b) Failure to measure in the correct time will cause the UE to        transmit in CG-SDT occasions where it should not be allowed to        transmit.

IV. Other Exemplary Considerations

As used in this application, the term “circuitry” may refer to one ormore or all of the following:

-   -   (a) hardware-only circuit implementations (such as        implementations in only analog and/or digital circuitry) and    -   (b) combinations of hardware circuits and software, such as (as        applicable): (i) a combination of analog and/or digital hardware        circuit(s) with software/firmware and (ii) any portions of        hardware processor(s) with software (including digital signal        processor(s)), software, and memory(ies) that work together to        cause an apparatus, such as a mobile phone or server, to perform        various functions) and    -   (c) hardware circuit(s) and or processor(s), such as a        microprocessor(s) or a portion of a microprocessor(s), that        requires software (e.g., firmware) for operation, but the        software may not be present when it is not needed for operation.

This definition of circuitry applies to all uses of this term in thisapplication, including in any claims. As a further example, as used inthis application, the term circuitry also covers an implementation ofmerely a hardware circuit or processor (or multiple processors) orportion of a hardware circuit or processor and its (or their)accompanying software and/or firmware. The term circuitry also covers,for example and if applicable to the particular claim element, abaseband integrated circuit or processor integrated circuit for a mobiledevice or a similar integrated circuit in server, a cellular networkdevice, or other computing or network device.

Embodiments herein may be implemented in software (executed by one ormore processors), hardware (e.g., an application specific integratedcircuit), or a combination of software and hardware. In an exampleembodiment, the software (e.g., application logic, an instruction set)is maintained on any one of various conventional computer-readablemedia. In the context of this document, a “computer-readable medium” maybe any media or means that can contain, store, communicate, propagate ortransport the instructions for use by or in connection with aninstruction execution system, apparatus, or device, such as a computer,with one example of a computer described and depicted, e.g., in FIG. 1 .A computer-readable medium may comprise a computer-readable storagemedium (e.g., memories 125, 155, 171 or other device) that may be anymedia or means that can contain, store, and/or transport theinstructions for use by or in connection with an instruction executionsystem, apparatus, or device, such as a computer. A computer-readablestorage medium does not comprise propagating signals.

If desired, the different functions discussed herein may be performed ina different order and/or concurrently with each other. Furthermore, ifdesired, one or more of the above-described functions may be optional ormay be combined.

Although various aspects of the invention are set out in the independentclaims, other aspects of the invention comprise other combinations offeatures from the described embodiments and/or the dependent claims withthe features of the independent claims, and not solely the combinationsexplicitly set out in the claims.

It is also noted herein that while the above describes exampleembodiments of the invention, these descriptions should not be viewed ina limiting sense. Rather, there are several variations and modificationswhich may be made without departing from the scope of the presentinvention as defined in the appended claims.

The following abbreviations that may be found in the specificationand/or the drawing figures are defined as follows:

-   -   3GPP third generation partnership project    -   5G fifth generation    -   5GC 5G core network    -   AMF access and mobility management function    -   AT ATtention! command prefix for modem control, also known as        Hayes commands    -   CG configured grant    -   CG-SDT configured grant-SDT    -   CMD command    -   CU central unit    -   DL downlink (from network to UE)    -   DRB data radio bearer    -   DU distributed unit    -   DUT device under test    -   eNB (or eNodeB) evolved Node B (e.g., an LTE base station)    -   EN-DC E-UTRA-NR dual connectivity    -   en-gNB or En-gNB node providing NR user plane and control plane        protocol terminations towards the UE, and acting as secondary        node in EN-DC    -   E-UTRA evolved universal terrestrial radio access, i.e., the LTE        radio access technology    -   FR2 frequency range 2    -   gNB (or gNodeB) base station for 5G/NR, i.e., a node providing        NR user plane and control plane protocol terminations towards        the UE, and connected via the NG interface to the 5GC    -   I/F interface    -   incl or incl. including    -   LTE long term evolution    -   MAC medium access control    -   MME mobility management entity    -   MT mobile termination    -   ng or NG next generation    -   ng-eNB or NG-eNB next generation eNB    -   NR new radio    -   N/W or NW network    -   OTA over the air    -   PCell primary cell    -   PDCP packet data convergence protocol    -   PDSCH physical downlink shared channel    -   PDU protocol data unit    -   PHY physical layer    -   PRACH physical random access channel    -   RA random access    -   RAN radio access network    -   RAR random access response    -   RA-RNTI random access-radio network temporary identifier    -   Rel release    -   RLC radio link control    -   RRC radio resource control    -   RRH remote radio head    -   RRM radio resource management    -   RSRP Reference Signal Received Power    -   RU radio unit    -   Rx receiver    -   SCS subcarrier spacing    -   SDAP service data adaptation protocol    -   SDT small data transmission    -   SGW serving gateway    -   SMF session management function    -   SRS sounding reference signal    -   SS system simulator    -   SSB synchronization signal block    -   TA timing advance    -   TAC timing advance command    -   TS technical specification    -   TST test    -   Tx transmitter or transmit    -   Txm transmission    -   UE user equipment (e.g., a wireless, typically mobile device)    -   UL uplink (from UE to network)    -   UPF user plane function    -   V2X vehicle to everything    -   w/ with

1.-27. (canceled)
 28. An apparatus, comprising: one or more processors;and one or more memories including computer program code, wherein theone or more memories and the computer program code are configured, withthe one or more processors, to cause the apparatus to: configure a userequipment, by transmission from a testing equipment, at least part of aprocedure of performance testing of data transmission to be performedwhile the user equipment is in a radio resource control inactive state;and perform, by the testing equipment, the at least part of theprocedure of performance testing of data transmission while the userequipment is in the radio resource control inactive state; wherein theat least part of the procedure includes at least one of: triggering thedata transmission while the user equipment is in the radio resourcecontrol inactive state; transmitting one or more test data packages;controlling time that the user equipment starts to transmit, while inthe radio resource control inactive state, payload corresponding to atleast one of the one or more test data packages; verifying whether ornot conditions for the data transmission are met; or determining whetheror not the user equipment passed the performance testing, based on aresult of the verification of whether or not conditions for the datatransmission are met.
 29. An apparatus, comprising: one or moreprocessors; and one or more memories including computer program code,wherein the one or more memories and the computer program code areconfigured, with the one or more processors, to cause the apparatus to:receive, at a user equipment, a configuration of at least part of aprocedure of performance testing of data transmission, the procedure tobe performed while the user equipment is in a radio resource controlinactive state; and perform, at the user equipment, based on theconfiguration, the at least part of a procedure of performance testingof data transmission while the user equipment is in the radio resourcecontrol inactive state, wherein the at least part of the procedureincludes at least one of: receiving signaling of triggering the datatransmission; receiving one or more test data packages; starting totransmit payload corresponding to at least one of the received one ormore test data packages in radio resource control inactive state, basedon the configuration; or transmitting one or more measurement resultsbased on one or more corresponding measurements made at the userequipment.
 30. The apparatus according to claim 28, wherein the datatransmission comprises at least one of a small data transmission, aconfigured grant-small data transmission, a two-step random-access-smalldata transmission, or a four-step random-access-small data transmission.31. The apparatus according to claim 28, wherein the one or more testdata packages comprises one or more of the following: time of a firstdata transmission to be performed at the user equipment; a number ofrepetitions data transmissions to be performed at the user equipment; ortime between the repetitions.
 32. The apparatus according to claim 28,wherein one or more triggers used to determine when to perform the datatransmission comprise timing information for at least a first datatransmission.
 33. The apparatus according to claim 28, wherein the oneor more test data packages comprises one or more of the following:indication of a test mode to be used at the user equipment; orindication of timing of the data transmissions in relation to a commandused to trigger the data transmission.
 34. The apparatus according toclaim 28, wherein one or more triggers used to determine when to performthe data transmission comprise corresponding one or more commands fromthe testing equipment to the user equipment.
 35. The apparatus accordingto claim 28, wherein the one or more test data packages comprises one ormore of the following: indication of how many data transmissions are tobe performed; indication of at least one of multiple data formats; orindication of how many bytes are to be used for the data transmissions.36. The apparatus according to claim 28, wherein one or more triggersused to determine when to perform the data transmission comprisecorresponding one or more commands from the testing equipment to theuser equipment.
 37. The apparatus according to claim 28, wherein theperformance testing determines whether the user equipment obtains valuesof reference signal received power within specified measurement windows,wherein multiple power levels are used for different measurementwindows.
 38. The apparatus according to claim 28, wherein the at leastpart of the procedure comprises: changing, by the testing equipment,downlink transmission power level to values during predefined timeintervals such that at least one of testing conditions is used fordetecting whether the user equipment has performed measurements insideor outside the correct measurement windows.
 39. The apparatus accordingto claim 28, wherein there is a first measurement window in which afirst transmission power is transmitted in the procedure from thetesting equipment, and the conditions for the data transmission compriseat least one of: a first condition comprises a validation condition fortiming advance is satisfied, wherein a second transmit power in a secondmeasurement window is such that |the second transmit power—the firsttransmit power| is not greater than a threshold and the datatransmission is allowed; a second condition comprises the validationcondition for timing advance is not satisfied, wherein the secondtransmit power in the second measurement window is such that |the secondtransmit power−the first transmit power| is greater than the thresholdand the data transmission is not allowed; and a third conditioncomprises the validation condition for timing advance is not satisfied,wherein the second transmit power in the second window is such that |thesecond transmit power−the first transmit power| is greater than thethreshold, and the data transmission is not allowed, and a thirdtransmit power outside the first measurement window is chosen such that|the second transmit power−third transmit power| is not greater than thethreshold and if the reference signal is measured outside of the firstmeasurement window the validation condition for the timing advance wouldbe satisfied; and a fourth condition, comprises the validation conditionfor timing advance is not satisfied, wherein a third transmit powertransmitted from the testing equipment before the start of the secondmeasurement window, the second transmit power in the second measurementwindow is such that |the second transmit power−the first transmit power|is greater than the threshold, and the data transmission is not allowedand wherein a third transmit power before the start of the secondmeasurement window is chosen such that |the second transmit power−thethird transmit power| is not greater than the threshold.
 40. Anapparatus, comprising: one or more processors; and one or more memoriesincluding computer program code, wherein the one or more memories andthe computer program code are configured, with the one or moreprocessors, to cause the apparatus to: configuring a user equipment, bytransmission from a testing equipment, at least part of a procedure tobe performed while the user equipment is in a radio resource controlinactive state; performing, by the testing equipment, the at least partof the procedure of performance testing of data transmission while theuser equipment is in the radio resource control inactive state, whereinthe at least part of the procedure is configured to start with a firsttransmit power level, which is changed to a second transmit power levelduring a measurement window to be used at the user equipment formeasuring one or more reference signals, and the at least part of theprocedure is configured to change transmission power back to the firstpower level when the user equipment is expected to perform measurementin the measurement window; and verifying whether or not one or moreconditions for the data transmission are met.
 41. The apparatusaccording to claim 40, wherein: the measurement window is a firstmeasurement window; the performing, by the testing equipment, the atleast part of the procedure of performance testing of data transmissionwhile the user equipment is in the radio resource control inactive statecomprises changing from the first transmit power level to a thirdtransmit power level during a second measurement window to be used atthe user equipment for measuring one or more reference signals, thesecond measurement window being later in time than the first measurementwindow; and the verifying whether or not one or more conditions for thedata transmission are met comprises receiving the data transmission fromthe user equipment and determining whether the transmission andcorresponding timing met the one or more conditions corresponding to oneor both of the first or second measurement window. 42.-47. (canceled)48. The apparatus according to claim 29, wherein the data transmissioncomprises at least one of a small data transmission, a configuredgrant-small data transmission, a two-step random-access-small datatransmission, or a four-step random-access-small data transmission. 49.The apparatus according to claim 29, wherein the one or more test datapackages comprises one or more of the following: time of a first datatransmission to be performed at the user equipment; a number ofrepetitions data transmissions to be performed at the user equipment; ortime between the repetitions.
 50. The apparatus according to claim 29,wherein one or more triggers used to determine when to perform the datatransmission comprise timing information for at least a first datatransmission.
 51. The apparatus according to claim 29, wherein the oneor more test data packages comprises one or more of the following:indication of a test mode to be used at the user equipment; orindication of timing of the data transmissions in relation to a commandused to trigger the data transmission.
 52. The apparatus according toclaim 29, wherein the one or more test data packages comprises one ormore of the following: indication of how many data transmissions are tobe performed; indication of at least one of multiple data formats; orindication of how many bytes are to be used for the data transmissions.53. The apparatus according to claim 29, wherein there is a firstmeasurement window in which a first transmission power is transmitted inthe procedure from the testing equipment, and the conditions for thedata transmission comprise at least one of: a first condition comprisesa validation condition for timing advance is satisfied, wherein a secondtransmit power in a second measurement window is such that |the secondtransmit power−the first transmit power| is not greater than a thresholdand the data transmission is allowed; a second condition comprises thevalidation condition for timing advance is not satisfied, wherein thesecond transmit power in the second measurement window is such that |thesecond transmit power−the first transmit power| is greater than thethreshold and the data transmission is not allowed; and a thirdcondition comprises the validation condition for timing advance is notsatisfied, wherein the second transmit power in the second window issuch that |the second transmit power−the first transmit power| isgreater than the threshold, and the data transmission is not allowed,and a third transmit power outside the first measurement window ischosen such that |the second transmit power−third transmit power| is notgreater than the threshold and if the reference signal is measuredoutside of the first measurement window the validation condition for thetiming advance would be satisfied; and a fourth condition, comprises thevalidation condition for timing advance is not satisfied, wherein athird transmit power transmitted from the testing equipment before thestart of the second measurement window, the second transmit power in thesecond measurement window is such that |the second transmit power−thefirst transmit power| is greater than the threshold, and the datatransmission is not allowed and wherein a third transmit power beforethe start of the second measurement window is chosen such that |thesecond transmit power−the third transmit power| is not greater than thethreshold.